Premier Texas LinuxFest 2010. Today's data centers are more dynamic than ever before. New hardware appears and disappears regularly, servers are virtualized and move in and out of the data center. Fortunately there is an open source tool that makes this all manageable and allows you to monitor your network, wherever it is. Zenoss Core is a free and open source (GPLv2) IT monitoring solution written in Python that has been downloaded over 1 million times and used in over 25,000 organizations worldwide.